36 lines
1.1 KiB
Plaintext
36 lines
1.1 KiB
Plaintext
# Print out a (global variable) string to stdout.
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#
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# To run:
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# $ bootstrap/bootstrap translate ex6.subx -o ex6
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# $ bootstrap/bootstrap run ex6
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# Hello, world!
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== code
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# . op subop mod rm32 base index scale r32
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# . 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes
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Entry:
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# write(stdout, X, Size)
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# . fd = 1 (stdout)
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bb/copy-to-ebx 1/imm32
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# . initialize X (location to write result to)
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b9/copy-to-ecx X/imm32
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# . initialize Size
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8b/copy 0/mod/indirect 5/rm32/.disp32 . . 2/r32/edx Size/disp32 . # copy *Size to edx
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# . syscall
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e8/call syscall_write/disp32
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# exit(ebx)
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e8/call syscall_exit/disp32
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== data
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Size: # size of string
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0x0d/imm32 # 13
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X: # string to print
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48 65 6c 6c 6f 20 77 6f 72 6c 64 21 0a 00
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# H e l l o ␣ w o r l d ! newline null
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# . . vim:nowrap:textwidth=0
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